This invention is directed to a lid for covering the top opening of a trash receptacle and more particularly to a thermoformed lid having a two piece vacuum formed construction and formed to include a specially configured arrangement for stiffening the center as well as the front, rear and side edges of the lid.
Steel lids have been used to cover trash receptacles but such lids are expensive to fabricate and have a disadvantage that they are relatively easily damaged in mechanical handling. They also have a disadvantage in that they are heavy and pose a hazard to the user loading trash into the receptacle. Another disadvantage is that such lids are difficult to repair should they become damaged. As a result of the difficulty of repair it is not unusual that these lids go unrepaired with a consequence that the receptacle is not effectively sealed when not in use.
Refuse containers are typically located out of doors where they are exposed to the weather. One problem is that steel lids are subject to rust. It is highly desirable to prevent rainwater which invariably collects on horizontal surfaces of such covers, from entering the containers first because of mere water volume weight and second because of problems added to the disposition of waste materials if they are soggy with or floating in polluted water.
Lightweight non-metallic receptacle covers are known and illustrated by U.S. Pat. Nos. 4,151,928 issuing May 1, 1979 to Fagliano et al., 4,158,424 issuing June 19, 1979 to Carmack, 4,445,623 issuing May 1, 1984 to Kolling et al. and 4,456,141 issuing June 26, 1984 to Pamment. While the cover shown in each of these patents may have been suitable for its intended use, a lightweight yet rigidly reinforced plastic cover would be desirable.
This invention provides an improved cover for use with a trash receptacle, the cover being integrally molded of plastic sheet material to include a hinge mounting arrangement adjacent to the rear edge of the cover, and stiffening ribs specially configured for reinforcing the central section as well as the front edge, the rear edge and the sides of the cover. The cover is constructed from two planar sheets of plastic, which sheets are first vacuum thermoformed to include stiffening ribs and then pressed together whereby to weld the sheet edges together and define a substantially sealed interior. The stiffening ribs from the lower sheet intersect with the ribs on the upper sheet whereby the ribs from one sheet are welded to the other sheet and, at least in part, welded to the ribs of the other sheet.
Additional rigidifying is provided by the unique arrangement of ribs. Peripheral portions of the edges from each of the two sheets are welded together, first to form a flange to maintain the shape of the cover, seal the cover periphery, and provide channel to drain water from the cover, and second to form a plurality of laterally spaced U-shaped hinge housings across the rear edge, the load bearing housings and flange thus being of double thickness. Further, lateral ribs extend upwardly from each of the sheets adjacent the front of the cover, the rib from the bottom sheet being interfitted into the rib of the upper sheet and welded thereto, the ends of the rib on the upper sheet being curled to assure a locked fitment with the rib on the lower sheet.
Further a post extends from the lower sheet for welded fitment within and to the walls of a receptacle formed by cross-ribs on the upper sheet, thus rigidifying the central portion of the cover.
Such a cover is lightweight yet durable, is capable of sustaining abuse during its use and provides an inexpensive cover for trash bins. The integral specially stiffened cover effectively seals the open top of a receptacle without the necessity of having complex flanges for securing the cover to the receptacle. Further, the sealed twin sheet construction and specially configured ribs cooperate to provide a reinforced cover which inhibits buckling if stood upon and inhibits twisting or torsional bending. When welded together, the sheets and ribs cooperate to form a box beam construction that obviates the need for separate, but additional, reinforcement members. Additionally, the lightweight cover will diminish potential harm to a user if the lid should inadvertently fall.
The foregoing and other objects will become more apparent when viewed in light of accompanying drawings and following detailed description wherein: